﻿# encoding:utf-8
# 测试字符串拼接常用的 join

arr = []
arr.append('a')
arr.append('b')
arr.append('c')

# 逗号分隔
s = ','.join(arr)
print(s)
# 输出：a,b,c


# 逗号分隔，key = %s
s2 = ','.join('{}=%s'.format(k) for k in arr)
print(s2)
# 输出：a=%s,b=%s,c=%s